IEC 63098-2:2022

Transmitting and receiving equipment for radiocommunication - Radio-over-fibre technologies and their performance standard - Part 2: Radio-over-fibre-based fronthaul network for railway communication systems

IEC 63098-2:2022 provides the required performance with reliability and quality assurance of radio-over-fiber-based fronthaul networks for railway communication networks between trains and tracksides, as well as a design guide for network configuration. A high-speed train communication network comprises two parts: a back-end network and wireless access system to deliver data to train cars. In this back-end network, optical fiber communication-based networks are generally utilized to reduce the complexity of the radio access units set along the railway track, which delivers the signal wirelessly to the train car, wireless signals are generated and processed at a central office, and then are transported via an optical fiber network into the radio access units. A radio-over-fiber fronthaul network is configured to transport the wireless signal, which is applicable between a node base station and radio access units set at a trackside. The radio-over-fiber-based fronthaul link connects the node base station to the trackside radio access units and carries millimeter-wave subcarrier or intermediate frequency components to transmit high-capacity signals.

General Information

• Status: Published
• Publication Date: 06-Dec-2022
• ICS: 33.060.20 - Receiving and transmitting equipment
• Technical Committee: TC 103 - Transmitting and receiving equipment for radiocommunication
• Drafting Committee: WG 6 - TC 103/WG 6
• Current Stage: PPUB - Publication issued
• Start Date: 23-Dec-2022
• Completion Date: 07-Dec-2022

Standards Content (Sample)

IEC 63098-2 ®
Edition 1.0 2022-12
INTERNATIONAL
STANDARD
colour
inside
Transmitting and receiving equipment for radiocommunication – Radio-over-
fibre technologies and their performance standard –
Part 2: Radio-over-fibre-based fronthaul network for railway communication
systems
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IEC 63098-2 ®
Edition 1.0 2022-12
INTERNATIONAL
STANDARD
colour
inside
Transmitting and receiving equipment for radiocommunication – Radio-over-

fibre technologies and their performance standard –

Part 2: Radio-over-fibre-based fronthaul network for railway communication

systems
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 33.060.20 ISBN 978-2-8322-6056-2

– 2 – IEC 63098-2:2022  IEC 2022
CONTENTS
FOREWORD . 4
INTRODUCTION . 6
1 Scope . 7
2 Normative references . 7
3 Terms, definitions and abbreviated terms . 7
3.1 Terms and definitions . 7
3.2 Abbreviated terms . 8
4 Functional specification . 8
4.1 RoF fronthaul network . 8
4.2 RoF transmitter and receiver . 9
4.3 Operating environment . 9
5 Testing . 9
5.1 General . 9
5.2 Performance testing . 9
6 Environmental specifications . 9
6.1 General safety . 9
6.2 Laser safety . 10
6.3 Temperature and environment . 10
Annex A (normative) Specifications for RoF fronthaul networks in railway
communication systems . 11
A.1 Overview. 11
A.2 Diagrams . 12
A.2.1 Optical switch-based system . 12
A.2.2 WDM-based system . 12
A.3 Functional specification. 13
A.4 Testing . 14
A.4.1 General . 14
A.4.2 Performance testing. 14
Annex B (informative) Specifications for the DSB RoF transmitter for fronthaul
systems in railway communication systems . 15
B.1 Overview. 15
B.2 Diagrams . 16
B.3 Functional specification. 17
B.4 Testing . 17
B.4.1 General . 17
B.4.2 Characterization testing . 17
B.4.3 Performance testing. 17
Annex C (informative) Specifications for SSB RoF transmitter for fronthaul system in
railway communication systems . 18
C.1 Overview. 18
C.2 Diagrams . 18
C.3 Functional specification. 19
C.4 Testing . 19
C.4.1 General . 19
C.4.2 Characterization testing . 19
C.4.3 Performance testing. 19

Bibliography . 20

Figure 1 – Block diagram of RoF fronthaul network for a railway communication system . 9
Figure A.1 – Schematic diagram of a railway communication system . 11
Figure A.2 – Block diagram of optical-switch-based fronthaul network . 12
Figure A.3 – Block diagram of WDM-based fronthaul network . 13
Figure B.1 – Relative RF throughput of the DSB-modulated signals over some length of
the optical fibre at a centre frequency of 3 GHz and 15 GHz . 16
Figure B.2 – Block diagram of DSB RoF transmitter with (a) external modulation and

(b) direct modulation systems . 16
Figure B.3 – Block diagram of DSB RoF transmitter with (a) external modulation and
(b) direct modulation systems for the WDM-based network . 17
Figure C.1 – Block diagram of SSB RoF transmitter with (a) DSB E/O with an optical
filter, (b) DD-MZM-based system and (c) IQ-modulator-based systems . 18

Table 1 – Abbreviated terms . 8
Table 2 – Operating environment . 9
Table A.1 – Functional specification of the RoF fronthaul network . 14
Table A.2 – Performance test plan . 14
Table B.1 – Functional specification of DSB RoF transmitter . 17
Table C.1 – Functional specification of SSB RoF transmitter . 19

– 4 – IEC 63098-2:2022  IEC 2022
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
TRANSMITTING AND RECEIVING EQUIPMENT FOR
RADIOCOMMUNICATION – RADIO-OVER-FIBRE
TECHNOLOGIES AND THEIR PERFORMANCE STANDARD –

Part 2: Radio-over-fibre-based fronthaul network
for railway communication systems

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IEC 63098-2
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